Vibratory motor



June 17, 1941. R. KNOPP VIBRATORY MOTOR I 2 sheets-sn p 1 1 Y B 7 .H

2 m V M Illll- June 17, 1941. KNQPP 2,245,981

VIBRATORY MOTOR Filed March 27, 1939 2 Sheets-Sheet 2 4/2 /3 I INVENTOR.

- fi W Z W Isl/m 9 ATTORNEY5 JLflilbH UNITED STATES PATENT OFFICE VIBRATORY MOTOR Rudolph Knopp, St. Louis, Mo., assignor to Knapp-Monarch Company, St. Louis, Mo., a corporation of Missouri Application March 27,1939, Serial No. 264,378

4 Claims.

An object of my invention is to provide a vibratory motor of simple, durable and inexpensive construction and particularly adapted for operating a dry shaver of the type having a reciprocating cutter.

A further object is to provide a vibratory motor in which a vibratory armature arrangement is provided that eliminates all vibration of the casing for the motor and thereby makes the shaver considerably less tiresome to operate than the usual type having a single vibratory armature with the momentum of the armature tending to vibrate the casing of the shaver.

More specifically, it is my object to provide a vibratory motor that is designed with a pair of armatures of substantially equal mass, vibrations being imparted to the armatures simultaneously in opposite directions at all times whereby the momentum of one armature cancels out the momentum of the other one and thereby prevents any vibrations being imparted to the casing for the motor.

Still another object is to provide a pair of armatures which have core extensions terminating adjacent each other inside of a hollow coil adapted to be energized with alternating current so that only one air gap is provided between the two armatures and equal magnetic attraction of the armatures and therefore equal vibration of each relative to the other is secured to minimize undesirable transmission of the armature vibrations to the casing of the motor.

Still a further object is to provide means whereby the two armatures can both be connected to an actuating element for the shaver head and to provide a guard for the shaver head which may be readily slipped into position or removed from position as desired.

With these and other objects in view, my invention consists in the construction, arrangement and combination of the various parts of my device whereby the objects contemplated are attained, as hereinafter more fully set forth, pointed out in my claims and illustrated in the accompanying drawings, in which:

Figure l is an enlarged plan view of my vibratory motor as applied to a dry shaver with parts of the casing broken away and removed to show internal details of construction, a portion of one armature and the coil of the motor being shown in section.

Figure 2 is a sectional view on the line 2-2 of Figure 1.

Figure 3 is a sectional view on the line 3-3 of Figure 2, showing an actuating element for the cutter head.

Figure 4 is a sectional view on the line 4-4 of Figure 2 showing operative connections between the armatures of my vibratory motor and a crank shaft operated thereby.

Figure 5 is a similar view showing the parts in a different position as caused by energization of the coil of the motor.

Figure 6 is a diagrammatic view to show the position and relation of parts of the motor relative to each other; and

Figure 7 is a plan view partly in section of a modified form of vibratory motor.

On the accompanying drawings I have used the reference numeral ID to indicate a lower casing element and I2 2. cover element therefor. The cover I2 may be secured to the casing ID as by screws I3.

Within the casing I0 a coil I4 is mounted. It is wound on a tube l5 having end plates I6. Bracket extensions Il from the end plates I6 are secured as by screws I8 in the casing Ill. The coil I4 is thereby rigidly mounted in the casing.

The tube I5 provides a hollow center or bore for the coil I4 which receives core members or extensions I9 and 20 of armatures 2I and 22, respectively. The armatures are anchored at one end as by rivets 23 to a mounting block 24. The block 24 is secured by screws 25 to the casing Ill.

The armatures 2I and 22 are preferably of laminated construction and of sufllcient resilience to permit vibrations thereof even though upon energization of the coil I4 with alternating current one end of each armature is rigidly anchored as at 23 to the block 24. The core member 20 is provided with a socket 26 receiving a resilient bumper 21 of rubber or the like. The bumper 21 is adapted to engage the extension I9 and prevent rattling of the parts against each other. The degree of vibration may be adjusted by a set screw 28, the position of which is retained by a lock nut 29.

A cutter or dry shaver head 30 is mounted in one end of the casing Ill-I2 and includes an outer tubular member 3I and an inner tubular member 32. The inner member is reciprocable relative to the outer member and the two of them are provided with shearing slots such as shown in my Patent No. 2,077,331.

For reciprocating the inner cutter 32 I provide an actuating shaft 33 journalled in a bearing 34 for oscillating movement. It has an angularly extending radial arm 35 entering a slot 36 of the inner cutter.

At La lower end of the actuating shaft 33 is a crank arm 31 extending in opposite directions therefrom and carrying a pair of crank pins 38. The crank pins 38 are connected by links 39 with pins 40 extending from the upper ends of the armatures 2| and 22. In Figure 4 I show this mean of operative connection and show in dot and dash lines the relation of the radial arm 35 to the parts 37, 38, 39 and 40. It will be noted there is a substantial distance between the adjacent ends of the armatures 2| and 22. When they are brought toward each other as in Figure the arm 35 will swing counterclockwise and reversely when they move apart from each other it will swing clockwise. It is therefore obvious how the vibrations of the armatures 2| and 22 will impart oscillations to the shaft 33 and the actuating arm 35.

The armatures 2| and 22 are of substantially equal mass so that when they move in simultaneously opposite directions the momentum of one cancels out the momentum of the other and thereby prevents vibration of the casing Ill-l2 in the hand of the operator while using the shaver. The armature extensions or core members l9 and 20 extending into the hollow coil I4 terminate quite close to each other to maximize the vibrations imparted to the armatures by by the magnetic action of the coil l4 in response to energization by alternating current.

The upper ends of the armatures 2| and 22 also attract each other whenever the coil is energized with the degree of attraction rising and falling because of the alternating character of the current and the normal tendency of the armatures to assume their initially spread-apart position under the action of their inherent resistance to bending from their anchored position. The result is vibration at a frequency of 7200 per minute on 60 cycle alternating current.

I have provided a vibratory motor in which undesirable vibrations imparted to the casing are entirely eliminated. The two armatures have equal magnetic pull thereon as they are symmetrical and both subjected to the same magnetic field. The motion of the armatures is kept in synchronism by the crank and link connection I have devised.

The vibratory motor may be constructed as thus far described or in everal other form to secure the same results of elimination of vibration of the casing. By way of -an example I show in Figure 7 a modified form in which a base plate 4| is provided for mounting in the shaver casing. A block 42 is secured thereto and a pair of armatures 43 and 44 are secured to the block at one end of each armature, the other ends indicated at 45 constitute the pole faces for attraction toward each other. The armatures 43 and 44 each extend longitudinally through a coil, the one for the armature 43 being indicated at 46 and for the armature 44 being indicated at 41. The coils 46 and 41 are so wound that the adjacent ends of the coils are of opposite polarity so that the pole pieces 45 will be attracted toward each other. The pole pieces are provided with pins 40A adapted to cooperate with the type of actuating element shown in the previou figures and indicated at 33, 35, 31, 38 and 39.

The operation of the invention as shown in Figure 7 will be obvious. Here again the armatures 43 and 44 are of substantially equal mass so that when they move simultaneously in opposite directions each cancels out the momentum of the other as far as imparting vibrations to the casing for the motor is concerned.

I provide a guard 48 for the cutter head 30. This guard consists of a length of semi-tubular sheet metal or the like of slightly greater extent than a half-circle. The casing cover I2 is provided with the groove 49 while the casing in is provided with a groove 50 to receive the edges of the guard 48. A plate 5| forms part of the groove 50. The grooves converge toward the interior of the casing l8-l2 so as to receive the terminal edges of the guard 48 and so as to retain it in position when it is once slid endwise into the grooves. This construction forms a convenient arrangement to protect the cutter head against damage when not in use.

although I have illustrated my vibratory motor in connection with a dry shaver, it is obvious that it can also be used in other devices, such as electric hair clippers, electric scissors and the like. The necessary changes for adapting the motor to operate devices other than dry shavers as illustrated may be made without departing from the real spirit and purpose of my invention. The construction and arrangement of parts of the motor itself also may be changed within the scope of the invention. It is therefore my intention to cover by my claims such modified form of structure and use of mechanical equivalents as may be reasonably included within their scope.

I claim as my invention:

1. In a vibratory motor, a casing, a hollow coil therein intermediate the ends of said casing, an armature adjacent each end of said coil, one end of each of said armatures being anchored in said casing adjacent one end thereof whereby the other ends of said armatures are movable toward each other upon energization of said coil, core members extending from said armatures and into opposite ends of said coil to a position adjacent each other therein, a resilient bumper between said core members, a crank shaft oscillatably journalled in the other end of said casing, a crank arm on said crank shaft and link connections between the free ends of said armatures and said crank arm to impart movement to said crank arm and thereby oscillate said crank shaft upon energization of said coil with alternating current to cause vibration of said armatures.

2. In a vibratory motor, a coil, a casing therefor, an armature across each end of said coil, means for mounting one end of each armature in said casing for swinging movement of the other end thereof upon energization of said coil with alternating current whereupon said other ends move simultaneously toward and away from each other, extensions from said armatures entering said coil and terminating adjacent each other, one of sa d extensions having a socket, a resilient insert therein adapted to be engaged by the other extension to limit movement thereof toward the extension having said socket, an oscillatable actuating shaft journalled in said casing and operative connections between said shaft and said other ends of said armatures, comprising crank arms on said shaft and extending in opposite directions therefrom and link connections between said crank arms and said other ends of said armatures.

3. In a vibratory motor, a casing, a hollow coil therein intermediate the ends of said casing, an

w TFW armature adjacent each end of said coil, one end of each of said armatures being anchored in said casing adjacent one end thereof, said armatlges being resilient whereby the other ends of sai'ifarmatures are movable toward each other upon energization of said coil, core members extending from said armatures and into opposite ends of said coil to a position adjacent each other therein, a crank shaft oscillatably journalled in the other end of said casing, a crank arm on said crank shaft, and link connections between the free ends of said armatures and said crank arm to impart movement to said crank arm and thereby oscillate said crank shaft upon energization of said coil with alternating current to alternately increase and decrease the current in said coil and thereby cause vibration of said armatures.

4. In a vibratory motor, a coil, a casing therefor, a resilient armature across each end of said DLHnbl'l coil, means for anchoring one end of each armature in said casing, the resiliency of the armatures permitting swinging movement of the other ends thereof upon energization of said coil with alternating current whereupon said other ends move simultaneously toward and away from each other because of such resiliency and the alternate increase and decrease of the current in said coil due to the alternating characteristic of the current, extensions from said armatures enter ing said coil and terminating adjacent each other, an oscillatable actuating shaft journalled in said casing, and operative connections between said shaft and said other ends of said armatures comprising crank arms on said shaft and extending in opposite directions therefrom and link con nections between said crank arms and said othe ends of said armatures.

RUDOLPH IQN'OPP. 

